Do you know the difference between possessive, plural, and a contraction with a word ending in "S"?

Yep, I have a MA to teach ESL.

I am so bad at grammer. When I just looked at your question I was like WTH is she talking about, but then after I saw your examples I was like ok yes, I know what your talking about, and yes I know the difference between possessive, plural, and a contraction with a word ending in "S"

oh, and just because its possessive, and ends with an S, does not mean don't add that extra S! Oh, hm...that doesn't make sense.Must provide an example.

Example:

Thomas' toy = Wrong

Thomas's toy = Right

Yes I know the difference. I don't think they teach this to kids in school anymore, although I could be wrong. Maybe they just don't put as much emphasis on it.

Actually, the ' or the 's at the end of a singular noun ending in s are both correct:

http://www.grammar-monster.com/lessons/apostrophes_show_possession.htm

Exception to the Rule (Singular Nouns Ending s)
To make things even more complicated, singular words which end in s (e.g., Charles, Wales, Paris and Dickens) can end in just an apostrophe or 's when showing possession.

Examples:

It is Charles' birthday. It is Charles's birthday.
(both correct)

Another link, which clarifies better

http://englishplus.com/grammar/00000131.htm

If the singular noun ends with an s, add apostrophe s if the extra syllable is pronounced. If the extra syllable is not pronounced (or if it otherwise looks confusing to add apostrophe s), simply add an apostrophe.

Examples: the dress's hem
(Added syllable is pronounced.)

Lloyd Bridges' son
(Added syllable is not pronounced.)

Some authorities always add an apostrophe only to any word ending with s, regardless of its pronunciation. This is acceptable. Whichever standard you follow, be consistent.

Example: the dress' hem
(Word ends in s, pronunciation does not matter.)

Oh, absolutely and it drives me nuts when people don't! I actually saw something yesterday I'd never seen before. The truck stated that it was a licensed something but instead of it saying licensed it said license'd. I've never seen the apostrophe D at the end of a word. That's a new one on me. I took a picture and sent it to my sister. It was worth saving.

(Lots of snickering) Unfortunately, you're not going to cause a reduction in titles like "for the bfing mom's."

yep.

 I teach apostrophe's to my class at school. ROTFPML!!! (it was intentional!!)

I hate apostrophes. For some reason the children in school have an attack of the apostrophes and they put them in as many words as they can whether or not they belong!! I can guarantee that even after 20 minutes of teaching input using a variety of different teaching aids a child will still write "I can use apostrophe's correctly" as their title (despite it being on the board!)

Oh, and their, there and they're as well as which witch irritate me too!!

Oh please explain there, their and they're. So many moms don't get that right.